Metaraminol is a life-saving drug which is part of the class of peripheral cardiovascular analeptic drugs. It is a powerful sympathomimetic amine increasing the systolic and diastolic blood pressures. Its effect begins 1-2 minutes after the intravenous administration and about ten minutes after the intramuscular injection and lasts 20 minutes to one hour. Metaraminol has positive inotropic effect at the heart level and vasoconstrictor effect at the peripheral level. Thus, it is indicated for the prevention and treatment of acute hypotensive statuses that may arise, for example, as a result of spinal anesthesia. It is also indicated as additional treatment for hypotension and anaphylactic shock. Metaraminol is currently marketed in the form of its salt with L-tartaric acid (Metaraminol bi-L-tartrate), of the following formula
Metaraminol Bi-L-Tartrate
Therefore, Metaraminol bi-L-tartrate is the acidic L-tartrate of a chiral aminoalcohol whose brute formula is C9H13NO2, with general chemical name of 3-(2-amino-1-hydroxy-propyl)phenol.
Since there are two different stereocenters in the molecule of 3-(2-amino-1-hydroxy-propyl)phenol, four stereoisomers are possible associated in two pairs of enantiomers and are in diastereomeric relation (syn and anti) one to the other:

Metaraminol corresponds to the compound anti “1R,2S” among these four diastereomers and is the only one among the diastereomers showing the high biological activity described above.
Separating enantiomers and diastereomers is known being difficult and expensive. Therefore, there is the continuous need to find new stereoselective syntheses allowing to obtain compounds having more than one stereocenter, such as Metaraminol, not only with optimal yield but above all with satisfying enantiomeric and diastereomeric excesses.